Improvement in hand-drills



tntrd (gdatei SPENCER H. OSTROM, OF SCH-ENECTADY, NEW YORK.

Letters Patent No. 90,292, dated May 18, 1869.

IMPROVEMENT IN EAND-DRILLS.

The Schedule referred to in these Letters Patent and making pazt of the same.

To all whom tt may concern:

Be it known that I, SPENCER H. OsTnoM, of Schenectady, in the county of Schenectady, and State of New York, have invented a new and useful Improvement in Boring-Braces; and I do hereby declare the following to be a full, clear, and exact description thereof, which will enable those skilled in the art to make and use the same, reference being had to the accompanying drawing, forming `part of this specification, in which drawing* Figure l represents a sectional side elevation of this invention.

Figure 2 is a sectional plan thereof.

Similar letters indicate corresl'ionding parts.

This invention consists in the arrangement of a fi'iction-strap, having one of its ends fastened to the handle, and its other end to a swivel-arm, to which the handle is pivoted, and which turns loosely on the head of the brace, said friction-strap being made to embrace the head ofthe brace, in such a manner that by moving, the handle in one direction, the strap is made to clamp the head,and said head, together with the bit, or drill inserted therein, is compelled to turn, and by moving the handle in 'the opposite direction, the strap releases the head of the brace, and the bit, or drill remains stationary, while the handle is swung back ready for a subsequent motion.

A spring attached to the swivel-arm, and bearing on a stud rising from the handle, compensates for all lost motion of thehandle.

A representsthe head of my brace, which is provided with a socket, a., to receive the bit, or drill, and from which extends the screw b, which is tapped into the cap e, and serves to produce the requisite feedmotion of the drill.

To the head A is fitted the swivel-arm B, which turns loosely thereon, and which connects, by a pivot, d, with the handle C To the inner end of this handle is secured one end of a strap, e, which passes round the head A, and has its other end fastened to the swivel-arm B, as shown in figs. l and 2 of the drawing, so that by turning or moving the handle in the direction of arrow l, the strap is caused to clamp the head, and thereby said head is compelled to turn with the handle, but by swinging the handle in the direction of arrow 2, the strap releases the head, and the handle turns, while the head remains 'station-ary.

The strap e is, by preference, made of spring-steel, and it is so applied that its inherent elasticity will keep the handle in proper position to prevent lost motion in the implement, but said strap may be made of any suitable flexible material.

An additional spring, j, which is secured in the swivel-arm B, and bears against a stud, g, projecting from the handle G, serves to throw the handle in such a position that the strap e clamps the head A, and by these means all dead motion of the implement is` avoided.

By this arrangement, a boring-brace is produced i teeth, and by the blows created when the pawl strikes a tooth, the working-parts ofthe brace are caused to wear out in a 'short time.

My brace can be used iu any place where the handle can be moved back and forth, whether the motion allowed to said handle be large or small, and the full motion of the handle is always transmitted to the drill.

Havingl thus described my invention,

What I claim as new, and desire to secure by Letters Patent, is-.

The spring f, in combination with the strap e, head A, swivel-arm B, and handle '0, substantially as set forth.

SPENCER H. OSTROM. W'itnesses:

J. VAN SAN'rvoonD, W. HAUFF. 

